SMPTE Color Bars technical question

BillyBoy wrote on 10/28/2002, 4:55 PM

Please take a look at the following page.

http://www.wideopenwest.com/%7Ewvg/color%20bar.htm

Who can give a technical answer why the values on the two color bar charts are different?

Comments

Tyler.Durden wrote on 10/28/2002, 6:07 PM

Technically, the images are different colors...

Whatcha need to know?

The charts (tables?) seem to reflect the color values depicted in the images...

The first set o bars looks like DV values to me (0-255), the second look like RGB values of NTSC standard colors (16-235).

And whatzup with that grey chip? Wherdja find them thar bars?

MPH

PS looks like ya got a typo in the NTSC table's blue column

actvman wrote on 10/28/2002, 7:47 PM

The top set looks like 100% saturation bars (you in as much say so in the description, and the tables bears this out), and the bottom appears to be 75% saturation true SMPTE NTSC bars.

Old type 1 Sony machines could only handle 75% saturation. In fact, this remains the standard even for Beta machines. In the analog world, only MII offered full 100% chroma. So although the voltage on a MII and BETA CAV singals look similar, the dynamic range is quite different. MII did/does a much better job handling telecined material.

Chris